docs: def split_comments(comments):
      """Split COMMENTS into flag comments and other comments.  Flag
      comments are those that begin with '#,', e.g. '#,fuzzy'."""
      flags = []
      other = []
      for c in comments:
          if len(c) > 1 and c[1] == ',':
              flags.append(c)
          else:
              other.append(c)
      return flags, other